This invention relates to semiconductor memory devices and method of manufacture, and more particularly to a random access, read/write memory cell.
Semiconductor read/write memory cells are usually of the so-called one-transistor type as disclosed in my U.S. Pat. No. 4,055,444 or in pending application, Ser. No. 722,841, filed Sept. 13, 1976, both assigned to Texas Instruments. While these cells have permitted densities as high as 64K bits on a chip less than 1/30 sq. inch in size, the demand for even smaller cell sizes and higher densities is continuing. The cost of a semiconductor memory device of a given chip size, in a package of a standard number of pins, is constant regardless of what is on the chip. Thus, if density can be increased, the cost per bit decreases.
It is the principal object of this invention to provide an improved semiconductor memory cell. Another object is to provide a read/write memory of reduced cell size. An additional object is to provide a dense array of RAM cells, made by a more efficient method.